The 2001 Volvo V70 station wagon has the roof-mounted IC, or Inflatable Curtain, airbag system installed as standard equipment. The IC airbag system utilizes stored and pressured gases inside a sealed cylinder to inflate the airbag in a side-impact collision.

When the Volvo S80 sedan was introduced as a 1999 model, the January 1999 edition of the University of Extrication featured information on the car’s roof-mounted airbag system. This roof-mounted airbag that Volvo calls its IC, or Inflatable Curtain, is folded and stored along the edge of the roof rail on each side of the car. It is secured to the A-pillar at the front and attached to the roof rail at the C-pillar.

What was and still remains critically important for emergency responders to be aware of with the Volvo IC is that it is a stored gas inflator system. This means that the airbag inflates when a mix of gas, in this case argon and helium, discharges from a pressurized cylinder. The stored gas inflator cylinder is bolted directly to the inside of the C-pillar, exactly in our roof removal “cut zone.”

The IC airbag system deploys downward from the roof rail to blanket both the front-door and rear-door window areas. The stored gas inflator cylinder is positioned horizontally along the roof rail between the C- and D-pillars.

The location of these cylinders was the reason that our roof-cutting procedures have changed. Because of the roof-mounted Volvo airbag system and the others that have followed since the 1999 model year, responders are advised to first strip away the interior roof trim material prior to cutting any roof post. With the trim peeled back, this cylinder can be seen by rescuers before they accidentally cut into it.

Other automakers have followed suit with their roof-mounted side-impact airbag systems. Audi, Mercedes and Saturn, for example, also mount their stored gas inflators on the rear C-pillars as Volvo does. BMW mounts its roof airbag inflator cylinder inside the ends of the dashboard, level with the top door hinge. (This system was explained in the June 2001 edition of the University of Extrication).

The airbag ID for the IC, or Inflatable Curtain, system is a plastic trim piece snapped into place at the top of both B-pillars. In a frontal collision with airbag deployment, the seatbelt pre-tensioners will also operate. The concussion of the pre-tensioners firing typically will dislodge this trim piece. Look for the missing airbag on the floor.

When Volvo added the side-impact, roof-mounted IC system to its new 2001 model year V70 station wagon, the location of the stored gas inflator module changed. It is not mounted to the wagon’s C-pillar as you might expect. Instead, the V70 vehicle and the V70 Cross Country version both have their two inflator cylinders mounted horizontally, bolted to the roof rail at a point between the C- and D-pillars.

With the rear headliner peeled down slightly, the stored gas inflator module can be seen in its position on the roof rail. The “nozzle” of the cylinder vents the gas forward and into the airbag. The IC airbag deploys downward to completely cover the front-door window and the rear-door window.

Rescue personnel can strip the trim on all roof pillars of the V70 station wagon to check for the location of the stored gas inflator cylinder. It won’t be until the rear headliner is pulled down that the pressurized cylinder will be exposed.

The single most effective measure responders can take at a vehicle crash to reduce the possibility of accidental airbag deployment is to take away the electrical power of the vehicle. The increased use of stored gas inflator modules for side impact airbags justifies the additional tactic of peeling roof pillar trim and now in this case, peeling down a portion of the roof headliner, in an attempt to locate the pressurized cylinders. Once spotted, all pillar cutting or roof rail cutting can be done by working around the cylinders.

With doors, it’s “Try before you pry.” When roof posts are involved in a rescue evolution, now it’s “Strip before you rip.”

A detailed look at the actual stored gas cylinder secured to the roof rail. Note the location between the C- and D-pillars. The black cylinder-shaped object behind the inflator is the hydraulic piston for the tailgate lifter mechanism.